Nozzle ring assembly



Fine 8, 1965 R. w. KANIK 1- NOZZLE RING ASSEMBLY Filed April 22, 1963 INVENTOR. ROBERT W. KANIK Fig. 6 BY ATTORNEY 3,188,051 NOZZLE RING ASSEMBLY Robert W. Kanik, Milford, Mich, assignor to The Bendix Corporation, Oneida, N.Y., a corporation of Delaware Filed Apr. 22, 1963, Ser. No. 274,412 2 Claims. (Cl. 25378) This invention relates to turbines and more particularly concerns nozzle means for directing air or other fluid to the peripheral blades of an axial-flow turbine wheel.

An object of the present invention is to provide a nozzle ring assembly which is comprised of two nozzle rings and a plurality of nozzle elements easily assembled and mounted between said rings for giving inclined flow paths.

A further object is the provision of nozzle means for directing fluid to the peripheral blades of an axial-flow turbine with the nozzle means including elements having a transverse wall and depending side wall-s with the elements overlapping whereby the side walls of one element cooperate with the transverse wall of the overlapped element to provide an inlet, flow channel, and an outlet. A further object is to provide an improved nozzle ring assembly for an axial-flow turbine which is easily fabricated and includes overlapped sheet metal nozzle elements whereby a low cost assembly results.

An additional object is the provision of sheet-metal,

, arcuate U-channel nozzle elements which fit between nozzle rings and cooperate with each other to give an inclined flow path with a partially flared inlet.

The realization of the above objects along with the features and advantages of the invention will be apparent from the following description and the accompanying drawing in which:

FIGURE 1 is a cross-sectional view of the sheet metal nozzle element lengthwise through the transverse or cover wall and shows the configuration of a side wall and the flared inlet tab of the cover wall,

FIGURE 2 is a developed cross-sectional view of several nozzle elements to show the overlapping to provide a flow path,

FIGURE 3 is a plane view of the underside of the arcuate nozzle element and shows the flared inlet tab of the radially-inner wall depending from the cover Wall,

FIGURE 4 is a perspective view of the arcuate nozzle element and shows the generally U-shaped configuration and the side walls terminating as inclined edges,

FIGURE 5 is a vertical cross-sectional view of the nozzle ring assembly and is taken on plane slightly in front of the partially-flared inlet showing the cooperation between cover walls, and

FIGURE 6 is a plane view of half of the outlet or tur- =bine side of the nozzle ring assembly and shows the rectangular outlets formed by the overlapping nozzle elements mounted in the annular space between nozzle rings.

Referring to FIGURES 1-4, the sheet-metal, arcuate nozzle element 11 has generally U-shaped cross section and is basically comprised of three walls which are the arcuate top wall 13, the radially-inner depending side wall 15, and the radially-outer depending wall 17. Each areaate or curved side wall 15 and 17 respectively has generally-rectangular sections 19 and 21 and generally triangular sections 23 and 25. The arcuate transverse wall 13 has an outwardly-bent flare section 27 formed by making two short notches 29 and 31 at the intersection of the top or cover wall 13 and the two side walls 15 and 17. Another outwardly-bent flare section 33 is formed from the outer end or rear part of radially-inner side wall 15. The end 34 of wall 17 is left straight. From the developed view of FIGURE 2, it is apparent that the U-channel, nozzle elements 11 are so dimensionedthat with i United States Patent 0 3,188,651 Patented June 8, 1965 top Wall 13 and the outer end of the radially-outer side wall -17 and the bent sections 27 and 33.

The nozzle ring assembly of FIGURES 5 and 6 includes a ring of the overlapping nozzles 11 (above described) and inner and outer nozzle rings 51 and 53 with the sides of the nozzle elements bonded to the rings. The inner nozzle ring 51 includes a radially-extending wall 55 and an axially-extending section 57 and a radially-outwardly-extending, circular locating flange 59 providing circumferential mounting surface. The outer housing or nozzle ring 53 includes a turbine wheel housing section 61, an axially-extending section 63 and circular flange 65. With supplemental reference to FIGURE 2, it is apparent that the nozzle ring assembly provides a circular series of outlets 45 and inclined nozzle passages 43. The nozzle elements 11 are overlapped so that the inletpart of overlapping element is at about the midpoint of the overlapped element. The nozzle elements formed from steel sheet metal are positioned so that the inclined edges 35 and 37 of the triangular portions 23 and 25 of the side walls 15 and 17 and the radial edges 39 of the transverse wall 13 are in a common plane which corresponds to the plane of the downstream sides of the positioning or attaching flanges 59 and 61. The portions of the side walls abutting flanges 59 and 61 are bonded thereto by brazing. The flared tabs 27 and 33 together with the straight upstream end parts 34 and the parts of the overlapped cover walls 13 provide an easily-made, partiallyflared inlet 45 which gives less turbulence than standard straight vane construction.

The operation of the nozzle ring assembly is believed to be apparent from the foregoing. Thus, the assembly is mounted in a turbine unit with the turbine mounted so that the tips of its blades are surrounded by'the shroud or housing extension 61 of outer nozzle ring 53. Suitable housing means are provided to cooperate with the radial wall 55 of the inner nozzle ring 51 and with the upstream part of outer nozzle ring 53 to give a fluid supply chamber for supplying fluid to the nozzle inlets 45. The pressurized air will enter inlet 45 formed by the mid-portion of one cover wall 13 and the straight end 34 of the radiallyouter side wall 17, the flared end 33 of the radially-inner side Wall 15 and the flared inlet end 27 of the cover Wall 13 of the adjacent overlapping nozzle element 11. The pressurized air will flow in an arcuate, axially-inclined path 43 formed by the lower part of the overlapped cover wall 13 and side walls 15 and 17 and cover wall 13 for discharge from outlet 41. Outlet 41 is formed by the overlapped transverse wall edge 39 and the overlapping transverse wall edge 39 and the edges 35 and 37 of side Wall triangular sections 23 and 25. It is to be appreciated that the flow at the inlet 45 is less turbulent and the curved inlet edges provide a partially-flared inlet which gives high level of eiiiciency as compared to a standard vane nozzle.

From the foregoing, it can be realized that an inexpensive sheet metal nozzle element including a partially-flared inlet is simply formed and that the nozzle ring assembly is easily fabricated by overlapping the nozzle elements with the edges 35 and 37 in a common plane between the circular flanges 59 and 61 (and flush with the turbine sides thereof) of the inner and outer rings 51 and 53 and then bondihg the nozzle elements 11 to the positioning flanges.

It is to be understood that changes can be made in the disclosed structure by persons skilled in the art without departing from the invention as set forth in the appended claims.

What is claimed is:

1. A nozzle ring assembly for directing a gaseous medium at an angle to blades at the periphery of an axialflow turbine wheel comprised of:

an inner ring having a circumferential surface,

an outer ring having a circular surface facing said circumferential surface,

said circumferential surface and said circular surface being radially spaced a predetermined distance to provide an axially-extending annulus,

a plurality of arcuate nozzle elements formed from sheet metal and arranged in a ring in said annulus and having a generally U-shaped cross section,

each of said arcuate nozzle elements having an arcuate transverse wall having a front radial edge and a rear part and first and second depending side walls,

each of said first side walls being arcuate to fit against the circular surface of said outer ring thereby providing the nozzle elements with radially-outer side walls,

each of said second side walls being areuate to fit against the circumferential surface of said inner ring thereby providing the nozzle elements with radial-inner side walls,

each of said side walls including a rectangular section having rear part and side edge and a triangular section having inclined edge,

the inclined edge of each of said triangular sections merging to each of said front radial edge of said transverse wall,

said nozzle elements being attached to said inner ring and outer ring by connection at the radial-outer and radially-inner side walls,

said nozzle elements being arranged so that said inclined edges of said triangular sections and the radial edges of said transverse wall are in a common transverse plane to provide outlets,

said nozzle elements being further arranged so that the edges of said rectangular sections successively abut said transverse Walls to provide an inlet and by overlapping an inclined gas passage, and

said rear edge part of said transverse Wall being separated from its side walls and bent to give an out- Wardly flared end and said radially-inner wall having the rear part of. the rectangular section bent to be flared outwardly to provide a partially-flared inlet giving improved inlet flow.

2. The nozzle ring assembly according to claim 1 and being further characterized by:

said circular surface of said outer ring being provided by a narrow radially-inwardly-projecting flange,

said circumferential surface of said inner ring being provided by a narrow radially-outwardly-projecting flange at the turbine side of said inner ring structure, and

said nozzle elements being connected to said rings by the inclined edge parts of said triangular sections of said side walls being brazed to said flanges with the turbine sides of said flanges being in the same transverse plane as said inclined edges and said front radial edge.

References Cited by the Examiner FOREIGN PATENTS 899,599 10/44 France. 1,121,516 5/56 France.

456,566 2/28 Germany. 759,514 4/53 Germany. 879,487 6/53 Germany. 913,651 6/54 Germany.

JOSEPH H. BRANSON, 1a., Primary Examiner. 

1. A NOZZLE RING ASSEMBLY FOR DIRECTING A GASEOUS MEDIUM AT AN ANGLE TO BLADES AT THE PERIPHERY OF AN AXIALFLOW TURBINE WHEEL COMPRISED OF: AN INNER RING HAVING A CIRCUMFERENTIAL SURFACE, AN OUTER RING HAVING A CIRCULAR SURFACE FACING SAID CIRCUMFERENTIAL SURFACE, SAID CIRCUMFERENTIAL SURFACE AND SAID CIRCULAR SURFACE BEING RADIALLY SPACED A PREDETERMINED DISTANCE TO PROVIDE AN AXIALLY-EXTENDING ANNULUS, A PLURALITY OF ARCUATE NOZZLE ELEMENTS FORMED FROM SHEET METAL AND ARRANGED IN A RING IN SAID ANNULUS AND HAVING A GENERALLY U-SHAPED CROSS SECTION, EACH OF SAID ARCUATE NOZZLE ELEMENTS HAVING AN ARCUATE TRANSVERSE WALL HAVING A FRONT RADIAL EDGE AND A REAR PART AND FIRST AND SECOND DEPENDING SIDE WALLS, EACH OF SAID FIRST SIDE WALLS BEING ARCUATE TO FIT AGAINST THE CIRCULAR SURFACE OF SAID OUTER RING THEREBY PROVIDING THE NOZZLE ELEMENTS WITH RADIALLY-OUTER SIDE WALLS, EACH OF SAID SECOND SIDE WALLS BEING ARCUATE TO FIT AGAINST THE CIRCUMFERENTIAL SURFACE OF SAID INNER RING THEREBY PROVIDING THE NOZZLE ELEMENTS WITH RADIAL-INNER SIDE WALLS, EACH OF SAID SIDE WALLS INCLUDING A RECTANGULAR SECTION HAVING REAR PART AND SIDE EDGE AND A TRIANGULAR SECTION HAVING INCLINED EDGE, THE INCLINED EDGE OF EACH OF SAID TRIANGULAR SECTIONS MERGING TO EACH OF SAID FRONT RADIAL EDGE OF SAID TRANSVERSE WALL, SAID NOZZLE ELEMENTS BEING ATTACHED TO SAID INNER RING AND OUTER RING BY CONNECTION AT THE RADIAL-OUTER AND RADIALLY-INNER SIDE WALLS, SAID NOZZLE ELEMENTS BEING ARRANGED SO THAT SAID INCLINED EDGES OF SAID TRIANGULAR SECTIONS AND THE RADIAL EDGES OF SAID TRANSVERSE WALL ARE IN A COMMON TRANSVERSE PLANE TO PROVIDE OUTLETS, SAID NOZZLE ELEMENTS BEING FURTHER ARRANGED SO THAT THE EDGES OF SAID RECTANGULAR SECTIONS SUCCESSIVELY ABUT SAID TRANSVERSE WALLS TO PROVIDE AN INLET AND BY OVERLAPPING AN INCLINED GAS PASSAGE, AND SAID REAR EDGE PART OF SAID TRANSVERSE WALL BEING SEPARATED FROM ITS SIDE WALLS AND BENT TO GIVE AN OUTWARDLY FLARED END AND SAID RADIALLY-INNER WALL HAVING THE REAR PART OF THE RECTANGULAR SECTION BENT TO BE FLARED OUTWARDLY TO PROVIDE A PARTIALLY-FLARED INLET GIVING IMPROVED INLET FLOW. 